Derm Part 2 - lecture 7-12

Question 1

what are the most common pathogens of bacterial pyoderma

Answer 1

staph pseudintermedius (dog)
staph aureus (cats)

Question 2

true or false
pyodermas are never primary

Answer 2

true

Question 3

what are the 4 types of bacterial pyoderma

Answer 3

intertrigo (skin fold dermatitis)
pyotraumatic dermatitis (hot spot)
superficial pyoderma
deep pyoderma

Question 4

what is unique to pyotraumatic dermatitis “hot spots”? treatment?

Answer 4

no satellite lesion

2-4% chlorhexidine topical + treat underlying cause (i.e. flea hypersensitivity, otitis externa, allergies)

Question 5

what is the cause of superficial pyoderma? treatment?

Answer 5

no identifiable underlying cause, folliculitis
topical therapy

Question 6

differentials for folliculitis?

Answer 6

demodex
dermatophytosis
bacterial pyoderma

Question 7

lesions associated with a deep bacterial pyoderma? treatment?

Answer 7

ulcers & hemorrhage
topical treatment but longer (4-6 weeks)

Question 8

primary difference between the treatments of superficial and deep pyoderma?

Answer 8

superficial - treat 1 week past resolution
deep - treat 2 weeks past resolution

Question 9

how to diagnose bacterial pyoderma?

Answer 9

cytology
staph will be cocci
E.coli, Pseudomonas, Corynebacterium will be rods

Question 10

empirical therapy starters for bacterial pyoderma

Answer 10

1st gen cephs
clavamox
clindamycin

Question 11

what is Malassezia Pachydermatis?

Answer 11

lipophilic budding yeast
commensal organism
secondary colonizer
NO immune suppression

Question 12

Diagnosis of Malassezia Pachydermatis

Answer 12

moist/waxy areas = impression smear
dry areas = tape
stain with diff quick
examine in oil immersion

Question 13

topical treatment for Malassezia Pachydermatis

Answer 13

shampoo, wipes, sprays, mousses w/ 2% chlorhexidine & 1-2% miconazole or ketoconazole

Question 14

systemic treatments for Malassezia Pachydermatis

Answer 14

2-4 weeks of ketoconazole or terbinafine

Question 15

what is the most common dermatophyte

Answer 15

microsporum canis

Question 16

Microsporum canis natural host?

Answer 16

cats “stray kitten syndrome”

Question 17

what is the most common lesion in dogs with dermatophytes

Answer 17

fungal kerion

Question 18

if you see “rotten log” with spores around it, what do you suspect?

Answer 18

Microsporum canis

Question 19

Diagnostics for dermatophytes? which is the gold standard?

Answer 19

woods lamp (30-80% fluoresce)
trichogram
culture (gold standard) on DTM
PCR

Question 20

what do you expect to see on a positive dermatophyte culture?

Answer 20

red color change + white/beige growth

Question 21

how can you speciate dermatophytes? are these found on the host?

Answer 21

macroconidia
do NOT grow on the host

Question 22

dermatophyte treatment:
systemic (every +)?
topical (every + & every exposed)?
environmental?

Answer 22

systemic - itraconazole, terbinafine
topical - lime sulfur, imidazoles
environmental - clean

Question 23

how long should you treat dermatophytes?

Answer 23

until two consecutive negative cultures taken 1-2 weeks apart

Question 24

most common equine dermatophyte?

Answer 24

trichophyton equinum

Question 25

phases of the hair cycle

Answer 25

anagen - growth catagen - transition telogen - rest exogen - shed

Question 26

how can you diagnose endocrinopathy alopecia?

Answer 26

NOT skin biopsy, need endocrine testing

Question 27

how can you diagnose endocrine alopecia lookalikes?

Answer 27

skin biopsy!

Question 28

what endocrinopathy might you see cutaneous atrophy, striae, phlebectasia, calcinosis cutis

Answer 28

Cushings

Question 29

what endocrinopathy might you see alopecia over bridge of the nose, "rat tail", nasal or paw pad hyperkeratosis, acanthosis, ceruminous otitis

Answer 29

hypothyroidism

Question 30

what might you expect with endocrinopathy response to therapy?

Answer 30

worse before better initial hair regrowth is darker

Question 31

what endocrinopathy might you see with feminization, aspermatogenesis, prostatic disease and bone marrow hypoplasia?

Answer 31

sertoli cell tumor

Question 32

what endocrinopathy might you see gynecomastia and abnormal estrus cycles?

Answer 32

cystic ovaries

Question 33

if an owner is using topical estrogen cream, what might happen in their dog?

Answer 33

iatrogenic hyperestrogenism

Question 34

what endocrinopathy lookalike do you suspect with a young Pomeranian with alopecia

Answer 34

Alopecia X

Question 35

what endocrinopathy lookalike do you suspect with alopecia due to a severe illness/metabolic stress like fever, pregnancy, lactation, shock or drugs?

Answer 35

telogen effluvium

Question 36

If a dog was recently clipped and surgically scrubbed and now has no hair regrowth, what endocrinopathy lookalike do you suspect? what are some treatments?

Answer 36

post clipping alopecia low level laser

Question 37

what endocrinopathy lookalike do you suspect with a boxer or bulldog with alopecia along flanks and lateral thorax? what might this also be associated with?

Answer 37

canine flank alopecia seasonal - melatonin deficiency

Question 38

treatment for canine flank alopecia?

Answer 38

melatonin therapy low level laser

Question 39

what endocrinopathy lookalike do you suspect with a young doberman or silver lab with alopecia in dilute areas of their coat?

Answer 39

color dilution alopecia

Question 40

what weakens the hair shaft in color dilution alopecia?

Answer 40

macromelanosomes

Question 41

what is an aquired pattern alopecia found in young dachshunds, boston terriers, chihuahuas and whippets? treatment?

Answer 41

pattern baldness none - cosmetic

Question 42

generalized findings with lupus (3)?

Answer 42

1. interface dermatitis 2. basal keratinocyte apoptosis 3. dead reds w/ satellitosis

Question 43

what is the most common lupus in small animals?

Answer 43

discoid lupus erythematosus

Question 44

most common sites for discoid lupus erythematosus

Answer 44

nasal planum pinna perioral

Question 45

what is the top differential for mucocutaneous lupus erythematosus? how would you differentiate?

Answer 45

mucocutaneous pyoderma - do cytology and look for bacteria cytology, culture, treat for infection, biopsy if persists

Question 46

what breed is vesicular cutaneous lupus erythematosus found in?

Answer 46

collies and shetland sheepdogs

Question 47

what breed is exfoliative cutaneous lupus erythematosus found in?

Answer 47

german shorthair pointer due to autosomal recessive mutation

Question 48

common findings with systemic lupus erythematosus

Answer 48

fever polyarthritis proteinuria thrombocytopenia discoid rash

Question 49

what is the most specific ANA titer for SLE

Answer 49

nuclear ribonucleoprotein G (HnRNP G)

Question 50

treatment for lupus?

Answer 50

immune suppression via... tacrolimus 1% topical doxy/niacinamide steroids non-steroidal immunosuppresives apoquel sunscreen

Question 51

what is symmetric lupoid onychodystrophy?

Answer 51

idiopathic immunemediated disease that affects multiple nails

Question 52

how do you diagnose symmetric lupoid onychodystrophy?

Answer 52

clinical signs bc biopsy requires amputation of P3

Question 53

treatment for symmetric lupoid onychodystrophy?

Answer 53

slow & forever pentoxifylline fatty acids cyclosporine doxy/niacinamide steroids

Question 54

what is the most common autoimmune dermatologic disease in dogs and cats?

Answer 54

pemphigus foliaceus

Question 55

difference between pemphigus foliaceus and vulgaris?

Answer 55

foliaceus = superficial vulgaris = deep

Question 56

pemphigus foliaceus predilection sites in dogs? cats?

Answer 56

dogs - pinna, paw pad, planum cats - face, nail beds, nipples

Question 57

autoantibodies target what in pemphigus foliaceus?

Answer 57

desmosomes = acantholytic keratinocytes

Question 58

autoantibodies target what in pemphigus vulgaris?

Answer 58

hemidesmosomes = ulcerations

Question 59

differentials for acantholytic keratinocytes

Answer 59

pemphigus foliaceus bacterial pyoderma dermatophytosis

Question 60

how do you definitively diagnose pemphigus foliaceus?

Answer 60

biopsy

Question 61

pemphigus vulgaris predilection sites?

Answer 61

oral mucocutaneous junctions paws

Question 62

how do you definitively diagnose pemphigus vulgaris?

Answer 62

junctional biopsy should see "tombstone effect"

Question 63

pemphigus treatments

Answer 63

immunosuppression steroids (first line) cyclosporine (2nd)